title: Efficient activation of nucleoside phosphoramidites with 4,5-dicyanoimidazole during oligonucleotide synthesis.
abstract: A new activator for the coupling of phosphoramidites to the 5'-hydroxyl group during oligonucleotide synthesis is introduced. The observed time to complete coupling is twice as fast with 4, 5-dicyanoimidazole (DCI) as the activator, compared with 1 H -tetrazole. The effectiveness of DCI is thought to be based on its nucleophilicity. DCI is soluble in acetonitrile up to 1.1 M at room temperature and can be used as the sole coupling activator during routine automated solid phase synthesis of oligonucleotides. The addition of 0.1 M N -methylimidazole to 0.45 M 1 H -tetrazole also results in higher product yields during oligonucleotide synthesis than observed with 1 H -tetrazole alone.
authors.affiliation: NeXstar Technology Products, 2860 Wilderness Place, Boulder, CO 80301, USA.
authors.forename: C
authors.initials: C
authors.lastname: Vargeese
authors.forename: J
authors.initials: J
authors.lastname: Carter
authors.forename: J
authors.initials: J
authors.lastname: Yegge
authors.forename: S
authors.initials: S
authors.lastname: Krivjansky
authors.forename: A
authors.initials: A
authors.lastname: Settle
authors.forename: E
authors.initials: E
authors.lastname: Kropp
authors.forename: K
authors.initials: K
authors.lastname: Peterson
authors.forename: W
authors.initials: W
authors.lastname: Pieken
mesh_terms: D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D005069:Evaluation Studies as Topic; D007093:Imidazoles; D007202:Indicators and Reagents; D009705:Nucleosides / Q000138:chemical synthesis* / Q000737:chemistry; D009841:Oligonucleotides / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification; D009943:Organophosphorus Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D012995:Solubility; D013777:Tetrazoles
chemical_list: C110830:4,5-dicyanoimidazole; D007093:Imidazoles; D007202:Indicators and Reagents; D009705:Nucleosides; D009841:Oligonucleotides; D009943:Organophosphorus Compounds; D013777:Tetrazoles; C045574:1H-tetrazole